Building structure with separate floor and ceiling joists



9 L. HELFMAN ETAL I 3,537,221

BUILDING STRUCTURE WITH SEPARATE FLOOR AND CEILING JOISTS Filed June 19, 1967 as I 40 Q 7 INVENTORS 62 j l 0 LEROY HELFMAN AL A.$HACKET 42 60 ATTORNEYS United States Patent Ofice 3,537,221 Patented Nov. 3, 1970 3,537,221 BUILDING STRUCTURE WITH SEPARATE FLOOR AND CEILING JOISTS Leroy Helfman, 22638 Chatsford Circuit, Southfield,

Mich. 48075, and A1 A. Shacket, 23600 Marlow, Oak

Park, Mich. 48237 Filed June 19, 1967, Ser. No. 646,990 Int. Cl. E04b /12, 5/52 US. Cl. 52289 9 Claims ABSTRACT OF THE DISCLOSURE Building structure for separating a ceiling and a floor to prevent noise transmission directly through the floor and ceiling, including a plate, floor joists positioned on top of the plate, a floor secured to the top of the floor joists, ceiling joists extending parallel to the floor joists and centered therebetween, drop ceiling cradles supporting the ends of the ceiling joists from the plates with the bottom of the ceiling joists positioned below the top of the plate and the top of the ceiling joists positioned above the top of the plate and a ceiling secured to the bottom of the ceiling joists. Said drop ceiling cradles include an angle part adapted to be secured to the plate and an upwardly opening U-shaped part for receiving the end of a ceiling joist connected to the angle part. A portion of the angle part of the drop ceiling cradle may be used to space the floor joists from the ceiling joists.

BACKGROUND OF THE INVENTION Field of the invention The invention relates to building structures and refers more specifically to structure for separating the ceiling of a lower level and the floor of an upper level in wood frame apartment construction.

Description of the prior art In the past it has been the practice of the construction industry to secure the floor of an upper level and the ceiling of the level immediately below the upper level to the same joists. Such constructed methods have resulted in substantial sound transmittal from the floor of the upper level to the joists to the ceiling of the lower level. This sound transmittal is particularly objectionable in multi-story apartment construction.

SUMMARY OF THE INVENTION The present invention provides structure whereby the ceiling of the lower level is suspended beneath the joists for the floor of the upper level whereby sound transmittal between the two levels is maintained at a minimum. In the suspension of the ceiling, separate ceiling joists are provided extending parallel to and centrally of the floor joists. The separate ceiling joists are suspended at their ends in drop ceiling cradles.

The cradles provide for particularly simple, economical and eflicient construction of the building structure of the invention and may be used to space the floor joists if desired.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial transverse section view through a building structure constructed in accordance with the invention.

FIG. 2 is a partial section view of the building structure illustrated in FIG. 1 taken substantially on the line 22 in FIG. 1.

FIG. 3 is an enlarged perspective view of the drop ceiling cradle used in the building structure of FIGS. 1 and 2.

FIG. 4 is a perspective view of a modification of the cradle illustrated in FIGS. 1 through 3.

FIG. 5 is a reduced front elevation view of a modification of the cradle illustrated in FIG. 4.

FIG. 6 is a perspective view of another modification of the cradle illustrated in FIGS. 1 through 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown best in FIG. 1, the building structure 10 includes the usual wood frame including wall studs 12, double plate 14, floor joists 16 and floor 18. The ceiling 20 is supported on ceiling joists 24 positioned between the floor joists 16.

As shown, the studs 12 may be the usual two by four studs. In the usual manner the two by four studs 12 support a double two by four plate 14-.

The floor joists 16 are secured to the upper surface 26 of the plate 14. The usual cross bracing 28 is provided between the floor joists 16. The floor joists 16 may, for example, be wood two by eights.

The [floor 18 of, for example, an upper level in an apartment building includes the rough sub-floor 30 secured directly to the tops of the joists 16. The finished floor, tile or the like, 32 is secured over the rough floor 30.

As shown best in FIGS. 1 and 2, the ceiling joists 24 may for example be two by fours extending parallel to the floor joists 16 andtransversely of the plate 26. The joists 24 are hung from the plate 26 with their bottom surface 34 to which the ceiling 20 is secured positioned below the top surface 26 of the plate 14 by means of the drop ceiling cradles 38. The top of the ceiling joists 24 are thus lowered below the center of the door joists 16, permitting installation of the cross bracing 28, as shown best in FIG. 1. The ceiling structure 20, which may for example be lath and plaster, is then secured to the bottoms of the ceiling joists 24.

With such structure it will 'be seen that the floor 18 and the ceiling 20 are completely free from each other so that sound will not be transmitted directly from the floor 18 to the ceiling 20. The vibrations of the joists 16 will be taken up in the frame construction, including the plate 14. With the structure illustrated in FIGS. 1 and 2, which structure is very simple and economical, eflicient sound separation of vertically related apartments may 'be accomplished.

The drop ceiling cradle 38 is illustrated best in FIG. 3 and includes the angle part 40 and the upwardly opening U-shaped part 42. As shown in FIG. 3, the angle part 40 is secured to the plate 14 and the part 42 is supported by the angle part 40. The end of a joist 34 is supported by the U-shaped part 42.

' 3 The angle part 40 of the cradle 38, as shown in FIG. 3, 7

52 extending therebetween. The angle part 40 and the part 42 of the cradle 38 are connected along the lower edge of the portion 46 of the part 40 and one edge of the portion 52 of the part 42.

Nail openings 54 for securing the cradle 38 to the plate 14 and for securing the end of a ceiling joist to cradle 38 are Provided as required.

The modified form 56 of the drop ceiling cradle 38 illustrated in FIG. 4 is much the same as the cradle 38 illustrated in FIG. 3. Therefore the same reference numerals are used for similar parts thereof. In the modified cradle structure 56 illustrated in FIG. 4, the horizontal portion 44 and the vertical portion 46 of the angle part 40 are separated at both ends along the indicated edge 58. The ends 60 and 62 are then bent outwardly so that they are in surface-to-surface contact with the leg portions 48 and 50 of the U-shaped part 42 of the cradle 56. The U-shaped part 42 of the cradle is thus reinforced and made more rigid.

In the modified cradle structure 64, illustrated in FIG. 5, the same reference numerals are used to designate the same parts of the cradle structure as in cradle structures 38 and 56. In th modified cradle structure 64, the end 60 of the vertically extending portion 46 of the angle part 40 is lengthened and only the piece 66 is separated from the horizontally extending portion 44 of the angle part 40. The piece 66 secured to the vertically extending portion 46 of the cradle 64 provides an abutment against which a floor joist 16 may be positioned whereby positioning of the floor joist 16 in construction is automatic. This is particularly advantageous since the cradles 64 may be positioned on the plates 14 before they are erected so that neither the spacing of the floor joists 16 nor the ceiling joists 34 have to be determined when they are erected. Time is thus saved in erecting the joists and possible accidents are prevented.

The cradle 68, illustrated in FIG. 6, again includes essentially the same elements which have been given the same reference numerals. However, due to the construction of the cradle 68, the angle part has been separated into two pieces 70 and 72 which are connected along vertical fold lines 74 and 76, respectively. Due to the method of constructing the cradle 68, a bottom securing tab 78 is provided. It will be particularly noted that the separation of the parts 70 and 72 along the edge 80 is a diagonal separation, thus providing cradle strength where required.

It will be further noted with respect to each of the cradles 38, 56, 64 and 68 that each of the cradles may be produced from a single compact, flat sheet of metal by merely cutting and bending the flat sheet of metal. Thus, the cradles are particularly simple, economical and efficient.

While one embodiment of the invention has been disclosed in detail along with modifications thereof, it will :be understood that other embodiments and modifications are contemplated. Thus, for example, the nail holes 54 could be replaced by triangular portions struck from the metal of the cradles along two sides thereof and extending at right angles thereto, whereby nails would be unnecessary. It is the intention to include all embodiments and modifications of the invention as are defined by the appended claims within the scope of the invention.

What we claim as our invention is:

1. A drop ceiling cradle for use in supporting an end of a ceiling adjacent to a wall plate with the bottom of the ceiling joist below the top of the plate and the top of the ceiling joist above the top of the plate, including an angle part for securing the cradle to the plate having a first portion adapted to extend along the top of the plate and a second portion adapted to extend vertically along one side of the plate connected to the first portion at right angles thereto at one edge thereof and an upto the adjacent leg portion of the U-shaped part in surfaceto-surface contact therewith.

2. Structure as set forth in claim 1 wherein a piece of the angle part extends upwardly above the first portion thereof to provide an abutment surface against which joists may be spaced.

3. Building structure comprising a frame plate, floor joists positioned on and extending transversely of the frame plate on predetermined centers, ceiling joists extending parallel to the floor joists, a drop ceiling cradle supporting the ceiling joists with the bottom thereof below the top of the plate and with the top thereof above the top of the plate including an angle part securing the cradle to the plate having a first portion extending along the top of the plate and a second portion extending vertically along one side of the plate connected to the first portion at right angles thereto at one edge thereof and an upwardly opening U-shaped part connected to the angle part for receiving the end of a ceiling joist having parallel spaced apart leg portions and a connecting portion therebetween which connecting portion is connected to the lower edge of the second portion of the angle part, the first and second portions of the angle part of the cradle being separated for a distance inwardly from at least one end thereof to the adjacent leg portion of the U- shaped part and the second portion extending parallel to the adjacent leg portion of the U-shaped part in the surface-to-surface contact therewith, a floor secured to the top of the floor joists and a ceiling secured to the bottom of the ceiling joists whereby sound transmission between the floor and ceiling is minimized.

4. Structure as set forth in claim 3 wherein a portion of the angle part of the cradle extends to an adjacent floor joist whereby the cradle is used to space the floor joist.

5. A drop ceiling cradle for use in supporting an end of a ceiling joist adjacent to a wall plate with the bottom of the ceiling joist below the top of the plate and the top of the ceiling joist above the top of the plate, including an angle part for securing to the plate and an upwardly opening U-shaped part having legportionsand a connecting portion connected to the angle part for receiving the end of a ceiling joist, the angle part of the cradle being in two separate pieces connected to the leg portions of the U-shaped part along vertical fold lines so as to be in spaced apart relation, each of said. pieces including an upper portion adapted to extend horizontally over the top surface of a plate anda lower portion extending vertically along the lower portion of the leg portions of the U- shaped part and terminating centrally thereof in a connection at right angles to the upper portion of the angle part.

6. Structure as set forth in claim 5 and further including a tab secured to the connecting portion of the U- shaped part extending downwardly from one edge thereof parallel to the floor joists, a drop ceiling cradle for supporting the ceiling joists with the bottom thereof below the top of the plate and with the top thereof above the top of the plate including an angle part for securing to the plate and an upwardly opening U-shaped part having leg portions connected to the angle part for receiving the end of a ceiling joist, the angle part of the cradle being in two separate pieces connected to the leg portions of the U- shaped part along vertical fold lines so as to be in spaced apart relation, each of said pieces including an upper por- 10 tion extending horizontally over the top surface of the plate and a lower portion extending vertically along the lower portion of the leg portions of the U-shaped part and terminating centrally thereof in a connection at right angles to the upper portion of the angle part, a floor secured to the top of the floor joists and a ceiling secured to the bottom of the ceiling joists whereby sound transmission between the floor and ceiling is minimized.

9. Structure as set forth in claim 8, and further including a tab secured to the connecting portion of the U-shaped 6 part extending downwardly from one edge theerof in the plane of the vertically extending portion of the angle part of the cradle.

References Cited UNITED STATES PATENTS 666,918 1/ 1901 Butz 287-20.94 858,838 7/1907 Tuteur 52-702 956,347 4/1910 Heller 52-289 X 2,110,863 3/1938 Barnett 52-702 X FOREIGN PATENTS 435,226 9/1935 Great Britain.

OTHER REFERENCES Architectural Record, NAl, A66, p. 124, May 1946.

ALFRED C. PERHAM, Primary Examiner US. Cl. X.R. 

